Xmp Go Reference Documentation

Xmp

Current Version: 9.5.0.82

Chilkat XMP is a software component (SDK, toolkit, library, etc) for accessing, manipulating, and adding XMP metadata to JPEG and TIFF files.

Object Creation

xmp := chilkat.NewXmp()
...
xmp.DisposeXmp()

Properties

DebugLogFilePath
func (xmp *Xmp) DebugLogFilePath() string
func (xmp *Xmp) SetDebugLogFilePath(s string)

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

top
LastErrorHtml
func (xmp *Xmp) LastErrorHtml() string

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorText
func (xmp *Xmp) LastErrorText() string

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastErrorXml
func (xmp *Xmp) LastErrorXml() string

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

top
LastMethodSuccess
func (xmp *Xmp) LastMethodSuccess() bool
func (xmp *Xmp) SetLastMethodSuccess(b bool)
Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of true indicates success, a value of false indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = true and failure = false.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to true. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

top
NumEmbedded
func (xmp *Xmp) NumEmbedded() int

The number of XMP metadata documents found within the JPG or TIFF file loaded by LoadAppFile.

top
StructInnerDescrip
func (xmp *Xmp) StructInnerDescrip() bool
func (xmp *Xmp) SetStructInnerDescrip(b bool)

Determines whether structures are stored with rdf:parseType="Resource", or within an "rdf:Description" sub-node.

top
UncommonOptions
func (xmp *Xmp) UncommonOptions() string
func (xmp *Xmp) SetUncommonOptions(s string)
Introduced in version 9.5.0.80

A property to be used for future uncommon needs. The default value is the empty string.

top
VerboseLogging
func (xmp *Xmp) VerboseLogging() bool
func (xmp *Xmp) SetVerboseLogging(b bool)

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

top
Version
func (xmp *Xmp) Version() string

Version of the component/library, such as "9.5.0.63"

top

Methods

AddArray
func (xmp *Xmp) AddArray(xml *Xml, arrType string, propName string, values *StringArray) bool

Adds or replaces an XMP property array. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The 2nd argument specifies the array type, which can be "bag", "seq", or "alt". The property name should be prefixed with the namespace, such as "dc:subject".

More Information and Examples
top
AddNsMapping
func (xmp *Xmp) AddNsMapping(ns string, uri string)

Adds a namespace to URI mapping. When a property is added via AddSimpleString or any of the other methods, the property name is namespace qualified. When adding the first property in a namespace, the rdf:Description is automatically added and the URI is obtained from the namespace-to-URI mappings. The standard (and commonly used) namespace mappings are defined by default. This is only used if the namespace is custom or not already handled.

top
AddSimpleInt
func (xmp *Xmp) AddSimpleInt(iXml *Xml, propName string, propVal int) bool

Adds or updates an XMP integer property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as "tiff:XResolution".

top
AddSimpleStr
func (xmp *Xmp) AddSimpleStr(iXml *Xml, propName string, propVal string) bool

Adds or updates a simple XMP string property. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The property name should be prefixed with the namespace, such as "photoshop:Credit".

top
AddStructProp
func (xmp *Xmp) AddStructProp(iChilkatXml *Xml, structName string, propName string, propValue string) bool

Adds or updates an XMP structured property value. The XMP metadata to be updated is contained in the XML object passed in the 1st argument. The structure name should be prefixed with the namespace, such as "Iptc4xmpCore:CreatorContactInfo". The property name within the structure should also be prefixed with the namespace, such as "Iptc4xmpCore:CiAdrCity".

top
Append
func (xmp *Xmp) Append(iXml *Xml) bool

Appends a new XMP metadata file to the XMP object. Any XMPs appended via this method will be present in the file when SaveAppFile is called. Files containing XMP metadata typically only include a single XMP document, so this method is usually only called when adding XMP metadata to a file for the first time.

top
GetArray
func (xmp *Xmp) GetArray(iXml *Xml, propName string) *StringArray

Finds and returns an XMP array property. The property name should be prefixed with the namespace, such as "dc:subject".

Returns nil on failure

top
GetEmbedded
func (xmp *Xmp) GetEmbedded(index int) *Xml

Returns the Nth embedded XMP document as a Chilkat XML object.

Returns nil on failure

top
GetProperty
func (xmp *Xmp) GetProperty(iXml *Xml, propName string) *Xml

To be documented soon...

Returns nil on failure

top
GetSimpleInt
func (xmp *Xmp) GetSimpleInt(iXml *Xml, propName string) int

Finds and returns an XMP integer property. The property name should be prefixed with the namespace, such as "tiff:ResolutionUnit".

top
GetSimpleStr
func (xmp *Xmp) GetSimpleStr(iXml *Xml, propName string) *string

Finds and returns an XMP simple string property. The property name should be prefixed with the namespace, such as "photoshop:Source".

Returns nil on failure

More Information and Examples
top
GetStructPropNames
func (xmp *Xmp) GetStructPropNames(iXml *Xml, structName string) *StringArray

Returns the property names used by an exsting structure within an XMP document. The contents of the structure can be retrieved by calling GetStructValue for each property name returned by GetStructPropNames.

Returns nil on failure

top
GetStructValue
func (xmp *Xmp) GetStructValue(iXml *Xml, structName string, propName string) *string

Returns the value of a single item within an XMP structure property. Property names should always be prefixed with the namespace.

Returns nil on failure

More Information and Examples
top
LoadAppFile
func (xmp *Xmp) LoadAppFile(filename string) bool

Loads a TIFF or JPG file into the XMP object.

top
LoadFromBuffer
func (xmp *Xmp) LoadFromBuffer(fileData []byte, ext string) bool

Loads a JPG or TIFF from an byte buffer containing the image file data.

top
NewXmp
func (xmp *Xmp) NewXmp() *Xml

Creates and returns a new/empty XMP metadata document as a Chilkat XML object.

Returns nil on failure

More Information and Examples
top
RemoveAllEmbedded
func (xmp *Xmp) RemoveAllEmbedded() bool

Removes all XMP metadata documents from an XMP object. After calling this method, call SaveAppFile to rewrite the JPG or TIFF file with the XMP metadata removed.

Returns true for success, false for failure.

top
RemoveArray
func (xmp *Xmp) RemoveArray(iXml *Xml, propName string) bool

Removes an XMP array property from the XMP document.

top
RemoveNsMapping
func (xmp *Xmp) RemoveNsMapping(ns string)

Removes a namespace-to-URI mapping.

top
RemoveSimple
func (xmp *Xmp) RemoveSimple(iXml *Xml, propName string) bool

Removes a simple XMP property from the XMP document.

top
RemoveStruct
func (xmp *Xmp) RemoveStruct(iXml *Xml, structName string) bool

Removes an XMP structure property from the XMP document.

top
RemoveStructProp
func (xmp *Xmp) RemoveStructProp(iXml *Xml, structName string, propName string) bool

Removes a single member from an XMP structured property.

top
SaveAppFile
func (xmp *Xmp) SaveAppFile(filename string) bool

Persists all changes made to the XMP document(s) by saving the XMP object to a file. Changes made by adding, updating, or removing properties are not persisted to the filesystem until this is called.

top
SaveLastError
func (xmp *Xmp) SaveLastError(path string) bool

Saves the last-error information (the contents of LastErrorXml) to an XML formatted file.

Returns true for success, false for failure.

top
SaveToBuffer
func (xmp *Xmp) SaveToBuffer() []byte

Saves a JPG or TIFF image with updated XMP to a byte buffer.

Returns nil on failure

top
UnlockComponent
func (xmp *Xmp) UnlockComponent(unlockCode string) bool

Unlocks the XMP component at runtime. This must be called once at the beginning of your application. Passing an arbitrary value initiates a fully-functional 30-day trial. A purchased unlock code is required to use the component beyond 30 days.

top